以二维三角晶格介质柱光子晶体线缺陷波导为研究对象,通过平面波展开(PWE)法对光在波导中传输时的慢光特性进行了仿真分析,发现光子晶体的填充因子以及线缺陷中的柱子半径大小决定了慢光导模在光子带隙中的传输特性。随着填充因子的增大,光子晶体波导的导模群速度迅速减小。缺陷柱的半径大小对导模群速度的影响要强于填充比。通过调整填充因子和缺陷柱半径.得到了导模群速度小于0.01c的波导结构。结合慢光导模的群速度色散(GVD)特性分析,发现极慢光区域的GVD值位于10^5~10^6量级,能够保证光的高效传输。
The characteristics of slow light in the 2D triangular rods photonic crystal line defected waveguide have been investigated with plane wave expansion (PWE) method. It is found that the filling factor of the photonic crystal and the radius of defect rods decide the propagating characteristic of the guided mode in the photonic crystal band gap. The group velocity of the guided mode decreases rapidly as increasing the filling factor. The effect of radius of the defect rods on the group velocity is stronger than the former. The waveguide structure with group velocity smaller than 0.01 c is demonstrated through detuning the filling factor and defect rods size. Group velocity dispersion (GVD) of the slow light is analyzed, and it is found that the magnitude of GVD value in the area of ultra slow light is about 10^5- 10^6 and propagation with high efficiency can be guaranteed.